Over the years this area has been problematic. We resisted gluing the area for 20 years and have come to the conclusion that gluing is the only guaranteed solution.
It turns out that most of the cases we encounter are out of round at the number 8 main. I've measured .015" out of round. This problem is not restricted to mag cases only although the problem seems to be more prominent in these engines. The leaks are caused by oil transitioning from the case to the bearing which overpowers the o-ring and the leak occurs.
We use a
thin layer of ThreeBond 1211 in the entire saddle. So thin that you can see through it. This glue reduces the possibility of oil leaking from this joint. The factory knew this joint leaks and their cure was to divert the pressurized oil by way a groove cut in the bearing. As we all know, this sometimes is not enough.
